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99 Rx-300 Transmission Problem


atnak

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I purchased a 99 RX-300 AWD 1 1/2 years ago from a Lexus dealership. The car has has always been serviced by Lexus at every scheduled maintenance with records to prove. The car now has 73k miles and the transmission is going out. It started a week ago at a stop light......I gave it gas, but it didn't go anywhere for 3 or 4 seconds. Now the transmission has trouble shifting in all gears. The last short trip I made the car wouldn't go over 35 mph. The symptoms seem to be different with each drive - whining noise, clunking sounds, hard shifts, and sometimes no problems at all. I'm bringing it to an independent shop for repairs and will update with the estimate to fix. It's disappointing to see so many RX-300's with transmission problems. I should have read this site before making the purchase. This is my first step up from a Toyota to a Lexus and probably won't do it again. I'm not a car person, I just want a reliable, comfortable vehicle.

Update 12/12/06

Below is my complaint to the NHTSA, which includes the cost and details of my repair.

In August 2005 I purchased a 1999 Lexus AWD RX-300 with 60,000 miles from Northside Lexus in Houston. On 12/4/06 the transmission failed at 73,882 miles – the vehicle would not shift into any gear. Lexus dealers had replaced the transmission fluid at 31,385 miles and 59,134 miles. An independent transmission shop rebuilt the transmission for $3896 with the following parts: torque converter, overhaul kit, all steels, front planetary, sun gear, ring gear, rear planetary, bushing kit, and bearing kit. According to the shop, this failure has nothing to do with improper maintenance or driving, but is related to a poor transmission design. He reported common transmission problems with Lexus RX-300 vehicles. Lexus has not issued a recall or service notice for these transmissions, nor would Northside Lexus agree to reimburse any part of my repair. There are currently 19 pages of transmission issues reported at http://us.lexusownersclub.com/forums. Many reports link the problem to low capacity on the ATF oil pressure pump. These transmissions must be recalled and Lexus must reimburse consumers for these very expensive repairs.

UPDATE 12/26/06

My problems are multiplying. When I got the car out of the shop for rebuilding the transmission the ABS light was on. The transmission shop said they did not do anything to cause this problem and it's just a coincidence. Another repair shop says the right front ABS sensor is bad. Is there anything the transmission shop could have done to cause this ABS problem? What about disconnecting the battery and causing an electrical problem with the sensor?

Where is the sensor on this vehicle? On the transmission tailshaft?

Any help would be appreciated.

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I am so sorry, read the posts carefully, RXNC says approach the dealership firmly and tell them you expect them to replace the tranny on their dime. Dont get mad, just be very firm. In his posts he gives you how he approached it and was successful. Since you have had your service at Lexus, they may do a good will, faith replacement. If not run to a tranny shop, they are a lot cheaper. The dealer will charge you $4300 but the tranny shop may be considerably less. Good luck and dont forget to file a complaint with the NHTS board online about your failure, you will need your vin # of the vehicle.

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I purchased a 99 RX-300 AWD 1 1/2 years ago from a Lexus dealership. The car has has always been serviced by Lexus at every scheduled maintenance with records to prove. The car now has 73k miles and the transmission is going out. It started a week ago at a stop light......I gave it gas, but it didn't go anywhere for 3 or 4 seconds. Now the transmission has trouble shifting in all gears. The last short trip I made the car wouldn't go over 35 mph. The symptoms seem to be different with each drive - whining noise, clunking sounds, hard shifts, and sometimes no problems at all. I'm bringing it to an independent shop for repairs and will update with the estimate to fix. It's disappointing to see so many RX-300's with transmission problems. I should have read this site before making the purchase. This is my first step up from a Toyota to a Lexus and probably won't do it again. I'm not a car person, I just want a reliable, comfortable vehicle.

Lots of 99 MY RX300 transsales are failing prematurely, ~70,000 miles and above.

These failures are most likely the result of transaxle control firmware changes to help prevent or alleviate accidents resulting form loss of control due to engine compression braking on a low traction roadbed surface. Up until Toyota came to GOD, came to realize that engine compression braking could result in a hazardous driving experience on a FWD or front biased AWD vehicle, there was no easy way to avoid these circumstances.

Icy bridge deck ahead, icy spot ahead, QUICK, lift the throttle...!!

Oops, car just spun out of control because, in effect, you just threw a "road anchor" out in front of the vehicle

A goodly number of years ago the AAA starting recommending that FWD owners practice quickly shifting the transaxle into neutral in preparation for the day that the practice came to fruition.

Apparently some time before the 99 RX300 went into production Toyota engineers came to realize that their entire FWD product line had a serious safety related problem. So the shift pattern was changed (this is VERY well documented) such that upon FULL lift-throttle events the transaxle would UPSHIFT so as to significantly reduce the resulting level of engine compression braking on the front drive wheels.

For forever and a day automatic transmissions have made use of a fixed displacement hydraulic pump to provide the fluid pressure for engaging the various clutches and driving the servomechanisms needed. The sizing of that pump is somewhat critical since any level of "over-pumping" of fluid will result in wasted effort and be lost as HEAT via simply bypassing the excess flow back into the sump. Just like your power stearing pump and the engine oil lubrcating pump. In those case the critical sizing involves the capacity at low engine RPM and so the engineers must simply live with the excess pump capacity, HEAT, and the engine RPM rises higher and higher.

Why is that tidbit important?

Because now that you just previously lifted your foot from the gas pedal and the tranxaxle began, accordingly, an (enhanced feature) upshift sequence you might have, on rare occassion, the need to quickly re-apply gas pedal pressure. That traffic light changed to green, an opening appeared in the oncoming traffic you want to merge into, etc, etc.

Oops....

With the engine at idle the (fully optimized) fixed displacement ATF pump could only, just barely, supply enough flow for that in-process upshift, now you're asking it to provide enough flow/pressure for the upcoming downshift.

Sorry, it AIN'T GONNA HAPPEN!

So, each and every time one of these FULL lift-thottle events happened to you in your 99 RX300, followed by a need to quickly accelerate, there was additional wear and tear, unexpected wear and tear, to the transaxle clutchs' friction surfaces.

I cannot say about the 2000 RX300 model year, but by 2001 a larger fixed displacement ATF pump was being used so the new, safer, firmware version could remain in use and the clutch surfaces did not wear out prematurely.

The downside.

While the 2001 MY RX300s were shipped with no routine or scheduled transaxle maintainance required for the life of the vehicle as stated in the owners manual, that was quickly changed to a need for an ATF drain and flush every 15,000 miles. That extra ATF pump capacity definitely helped to alleviate the premature transaxle failures due to clutch wear, but now the extra ATF pumping capacity that wasn't needed 95% of the time resulted in overheating the ATF.

2004 MY, the RX330, a new FIX.

DBW, e-throttle, was adopted to prevent the engine RPM from rising until the older version, the original lower capacity fixed displacement ATF pump, could provide enough flow/pressure to fully and firmly seat the clutch surfaces the second time in quick succession.

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Lots of 99 MY RX300 transsales are failing prematurely, ~70,000 miles and above.

. . .

Apparently some time before the 99 RX300 went into production Toyota engineers came to realize that their entire FWD product line had a serious safety related problem. So the shift pattern was changed (this is VERY well documented) such that upon FULL lift-throttle events the transaxle would UPSHIFT so as to significantly reduce the resulting level of engine compression braking on the front drive wheels.. . .

So, each and every time one of these FULL lift-thottle events happened to you in your 99 RX300, followed by a need to quickly accelerate, there was additional wear and tear, unexpected wear and tear, to the transaxle clutchs' friction surfaces.

I cannot say about the 2000 RX300 model year, but by 2001 a larger fixed displacement ATF pump was being used so the new, safer, firmware version could remain in use and the clutch surfaces did not wear out prematurely.

The downside.

While the 2001 MY RX300s were shipped with no routine or scheduled transaxle maintainance required for the life of the vehicle as stated in the owners manual, that was quickly changed to a need for an ATF drain and flush every 15,000 miles. That extra ATF pump capacity definitely helped to alleviate the premature transaxle failures due to clutch wear, but now the extra ATF pumping capacity that wasn't needed 95% of the time resulted in overheating the ATF.

. . .

WW: (emphasis added to quote)

1. So is every Lift-throttle event when I approach a red light or stop sign causing this same excessive wear and tear then, or as you say the extra wear is only if one quickly needs to reaccelerate? It sounds like coasting to stops is not excessively wearing on the clutches?

2. Do you think I should flush my FWD trannsmission and replace fluid @~40k? Mine basically says no fluid changes until 90k or something - similar language is even on the dipstick.

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RXHound.

1. My best guess is that the initial upshift due to FULL lift-throttle is not unduly stressfull on the clutch surfaces, NO engine torque to create frictional forces, HEAT. It is the subsequent downshift, with no "reserve" ATF flow/pressure, during which the engine torque is already rising that results in premature transaxle failures of the early RX models.

2. I do my own oil/filter changes and at the same time always check other items, brake fluid level, power stearing pump, etc. It was at one of these intervals that I noticed the condition of my ATF. So my plan is to continue to check/watch the ATF condition and if it should again turn dark and look and smeel burned I will change it out again.

That would be my recommendation to anyone concerned.

I don't know if the later RX models, >2001, presumably with the higher capacity ATF pump, are experiencing any serious or notable level of premature failures. That being said it is NEVER a good idea to continue operating a transaxle with known ATF "breakdown", once it looks dark and odorous, smells burned.

So I would suspect that should the ATF not be changed out when it is appropriate to do so the transaxle just might be subject to a premature failure.

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